The counter-terrorism unit has taken charge of the case due to "new information and evidence" on the suspected murder of the former minister, the UK Home Secretary says.

British police said they had launched a murder investigation into the death of Ann Widdecombe, a 78-year-old former government minister whose death was announced earlier on Friday.

Home Affairs Minister Shabana Mahmood confirmed on Monday that there were reasons to believe there was a terrorist motive to the alleged crime.